1. Field of the Invention
The invention relates generally to a lightweight tension structure having a plurality of arches, and in particular, to a pavilion type tent structure having crossbars and flexible fabric membranes in tension between peripheral arches such that the tension may be maintained and the arches kept upright without additional support members or tension guide lines.
2. Summary of the Related Art
Fabric structures and enclosures are used in a variety of applications. Large fabric domes cover outdoor arenas, shopping malls, swimming pools, tennis courts and other locations having a need for a customized shelter. Specially designed fabric structures may be temporarily or permanently used for fairs, meeting halls, pavilions, barracks, and other similar applications. Smaller tents provide camping and residential shelters.
There is also an increasing demand throughout the world for residential dwellings that provide housing at a low cost. Numerous problems are encountered in providing adequate housing. These problems include, but are not limited to, the cost of the structure, the transportation and availability of materials, and the skilled labor requirements. The need exists for a fabric dwelling that is cost effective and convenient to build.
Fabric structures are also used extensively for commercial awnings and canopies to provide both shelter and promotional benefits to a business entity. In addition to the more traditional uses noted above, fabric structures may also be used for sculptures and other more artistic purposes.
In fabric structures, the proper tension must be maintained on the fabric to accommodate the intended application of such fabric structure. A number of different support structures and tensioning means have been developed to maintain the desired tension in a fabric structure. Most of the smaller or mid-sized fabric structures utilize a center support means with anchored guide lines attached to side supports in order to maintain the structure.
In many fabric structures, it is desirable to reduce or eliminate the center support means and guide lines needed to maintain a fabric at the proper tension and to minimize the overall support frame. Special ventilation systems to support the fabric are often required in such situations. In other cases, a complex frame is needed to support the fabric structure.
In U.S. Pat. No. 3,886,961 to Geiger et al, a portable structure utilizes the cooperation of flexible arches as compression members in the structure. The tensioned membrane is provided with stressed cables to brace the arches and form a rigid structure.
U.S. Pat. Nos. 3,909,993 and 4,092,992 to Huddle show additional structures using arched supports and means for making laminated arch members. The supports are forced apart in the crown area of the arch by the use of inclined arches or other tensioning means to support the structure.
A building structure including one polyhyparic surface formed of a continuous tensioned web coupled to structural members along its periphery is disclosed in U.S. Pat. No. 4,584,800 to Burt et al.
U.S. Pat. No. 4,886,084 to Lawrence et al. shows a panelized fabric-covered structure with removable and replaceable fabric panels, including an expandable frame having a plurality of frame members for holding a fabric panel.